A steam wand assembly

Abstract

There is disclosed herein a steam wand assembly (100) including: a steam wand body (102) defining a central longitudinal axis (112); a nozzle assembly (104) located at an end portion (108) of the steam wand body (102); a temperature sensor assembly located adjacent to the nozzle assembly (104), the temperature sensor assembly including: a main body (122) mounted to the steam wand body (102); a temperature sensor (120) mounted to the main body (122); a sensor seal (126) located between the temperature sensor (120) and the nozzle assembly (104); and a sensor holder (124) coupled to the main body (122) and the sensor seal (126) and adapted to secure the temperature sensor (120) within the steam wand body (102).

Description

A STEAM WAND ASSEMBLYCROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to Australian Patent Application No. 2024900642, filed on 12 March 2024. The entire disclosure of Australian Patent Application No. 2024900642 is hereby incorporated by reference in its entirety and for all purposes.FIELD

[0002] The present invention relates to devices that heat milk by steaming. In particular, the invention relates to steam wands that are attached to coffee machines and methods of forming the same.

[0003] The invention has been developed primarily for use with coffee machines, and will be described hereinafter with reference to these applications. However, it will be appreciated that the invention is not limited to this particular field of use, and may also be employed in other applications involving heating of liquids.BACKGROUND

[0004] Devices to heat milk by steaming so as to create froth and / or texture in the milk are known. Texturing is adding air bubbles to milk, and heated and textured milk is used to make milk-based coffee beverages such as cappuccinos and lattes. Conventional devices for steaming milk include steam wands that are attached to coffee making machines, such as an espresso machine. Such steam wands may include a built-in temperature sensor to detect the temperature of the milk during steaming.

[0005] Steam wands having built-in temperature sensors typically have a larger diameter (e.g. relative to steam wands without built-in temperature sensors) due to the size or length of the temperature sensor, the sealing around the temperature sensor, and / or the electrical and / or mechanical connections between the temperature sensor and the steam wand components (suchas the inner steam tube and the outer housing). These factors rely on a large amount of space within the steam wand, resulting in a steam wand with a large diameter.

[0006] Steam wands having large diameters may have one or more of the following disadvantages: when a user manually steams / froths the milk, the steam wand blocks the full view of the milk and thus the user may not be able to monitor the steaming / frothing process properly, thereby impacting the final quality of the steamed / frothed milk. Additionally, steam wands having large diameters may in turn require an overall increased steam wand length, in particular the distance between the steam tube and the nozzle outlets, which may cause condensation within the steam wand as more water (rather than steam) is pushed from the nozzle outlets to the milk. This may again decrease the final quality of the steamed / frothed milk.

[0007] The lower part of the steam wand may also become hot during the milk steaming / frothing process, which “cooks” the protein of the milk onto the steam wand, making it difficult to clean. This may also result in a wand temperature that is unsafe for the user to touch for various purposes, such as for cleaning. The integrity of the sealing of known steam wand constructions also typically relies on the user - i.e. when the nozzle part is removed from the steam wand (e.g. for cleaning purposes), the user is required to tighten the nozzle part up to seal the steam wand during re-assembly to ensure that the sealing is maintained.SUMMARY

[0008] It is an object of the present invention to substantially overcome, or at least ameliorate, one or more of the disadvantages of existing arrangements, or at least provide a useful alternative to existing arrangements.

[0009] In accordance with one aspect, there is provided a steam wand assembly including: a steam wand body defining a central longitudinal axis; a nozzle assembly located at an end portion of the steam wand body; a temperature sensor assembly located adjacent to the nozzle assembly, the temperature sensor assembly including: a main body mounted to the steam wand body; a temperature sensor mounted to the main body;a sensor seal located between the temperature sensor and the nozzle assembly; and a sensor holder coupled to the main body and the sensor seal and adapted to secure the temperature sensor within the steam wand body.

[0010] In one or more embodiments, the main body includes a cavity providing a steam path for delivery of steam to the nozzle assembly and a wiring path for electrical communication to the temperature sensor.

[0011] In one or more embodiments, the steam path includes a steam path outlet located in close proximity to the temperature sensor.

[0012] In one or more embodiments, the main body includes an inner wall portion to separate the steam path and the wiring path into two longitudinally adjacent portions.

[0013] In one or more embodiments, the inner wall portion includes one or more ramps to facilitate the separation between the steam path and the wiring path.

[0014] In one or more embodiments, the main body has a generally tubular arrangement having an upper plane, a central plane, and a lower plane, with the outer wall of the main body extending along the upper and lower planes.

[0015] In one or more embodiments, the inner wall portion extends diagonally between the upper plane and the lower plane to form a ramp.

[0016] In one or more embodiments, the inner wall portion extends diagonally from the upper plane to the central plane to form a first ramp, then linearly along the central plane, then diagonally from the central plane to the lower plane to form a second ramp.

[0017] In one or more embodiments, the temperature sensor is mounted to the main body so as to be centrally aligned with the steam wand body.

[0018] In one or more embodiments, the sensor holder is coupled to an outer portion of the sensor seal and an outer wall of the main body.

[0019] In one or more embodiments, the sensor holder includes one or more slots or openings adapted to receive one or more corresponding projections of the main body.

[0020] In one or more embodiments, the main body and the sensor holder cooperate to retain the sensor seal and the temperature sensor in place within the steam wand body.

[0021] In one or more embodiments, the temperature sensor and the sensor seal are attached directly to the main body.

[0022] In one or more embodiments, the nozzle assembly includes a nozzle body threadably coupled to the main body.

[0023] In one or more embodiments, the steam wand assembly further includes a nozzle seal located between the nozzle body and the main body for sealing the nozzle assembly.

[0024] In one or more embodiments, the main body is threadably coupled to an outer housing of the steam wand body.

[0025] In one or more embodiments, the main body is coupled to the outer housing by way of a locking nut.

[0026] In one or more embodiments, an inner bore wall of the outer housing includes a threaded portion and a relief channel that creates a shoulder adjacent the threaded portion.

[0027] In one or more embodiments, the steam wand assembly includes further a steam tube connected to the main body, the steam tube having an outlet located in close proximity to the temperature sensor.

[0028] In one or more embodiments, the main body, the sensor holder, and / or the nozzle body are formed from a high temperature polymer material.BRIEF DESCRIPTION OF THE DRAWINGS

[0029] For a more complete understanding of the present invention, exemplary embodiments of the invention are explained in more detail in the following description with reference to the accompanying drawing figures, in which like reference signs designate like parts and in which:

[0030] Figure l is a schematic side cross-sectional view of a steam wand assembly according to one embodiment, with an accompanying enlarged view;

[0031] Figure 2 is a schematic exploded view of the steam wand assembly shown in Figure 1;

[0032] Figure 3 is a schematic side cross-sectional view of the steam wand assembly shown in Figure 1, with various components removed;

[0033] Figure 4 is a further schematic side cross-sectional view of the steam wand assembly shown in Figure, with an accompanying enlarged view;

[0034] Figure 5 is a schematic side cross-sectional view of a steam wand assembly according to another embodiment, with an accompanying enlarged view;

[0035] Figure 6 is a schematic exploded view of the steam wand assembly shown in Figure 5;

[0036] Figure 7 is a schematic side cross-sectional view of the steam wand assembly shown in Figure 5, with various components removed;

[0037] Figure 8 is a schematic side cross-sectional view of a steam wand assembly according to another embodiment, with an accompanying enlarged view;

[0038] Figure 9 is a schematic side cross-sectional view of a steam wand assembly according to another embodiment, with an accompanying enlarged view;

[0039] Figure 10 is a schematic side cross-sectional view of a steam wand assembly according to another embodiment, with an accompanying enlarged view;

[0040] Figure 11 is a schematic exploded view of the steam wand assembly shown in Figure 10;

[0041] Figure 12 is a schematic side cross-sectional view of a steam wand assembly according to another embodiment, with an accompanying enlarged view;

[0042] Figure 13 is a schematic exploded view of the steam wand assembly shown in Figure 12;

[0043] Figure 14 is a schematic side view of the steam wand assembly shown in Figure 12, with various components removed;

[0044] Figure 15 is a schematic side cross-sectional view of the steam wand assembly along line A- A shown in Figure 14;

[0045] Figure 16 is a further schematic side view of the steam wand assembly shown in Figure 12, with various components removed;

[0046] Figure 17 is a schematic side cross-sectional view of the steam wand assembly along line B-B shown in Figure 16;

[0047] Figure 18 a schematic exploded view of the moulded part of a main body shown with accompanying mould tools;

[0048] Figure 19 a schematic side cross-sectional view of a moulded part of a main body; and

[0049] Figure 20 is a schematic side cross-sectional view of a post-processed part of a main body.DETAILED DESCRIPTION

[0050] In Figures 1 to 4 of the accompanying drawings, there is schematically depicted an embodiment of a steam wand assembly 100 having a steam wand body 102 and a nozzle assembly 104. The steam wand body 102 has a first end portion 106 attached to a coffee machine (not shown) and a second end portion 108 from which the nozzle assembly 104 extends or is disposed. For the purposes of this specification, the steam wand assembly 100 and variousalternative embodiments will be described in relation to applications involving the provision of steam and / or air from a milk frothing device or a milk frothing module of a coffee machine to created steamed / frothed milk. It will, however, be appreciated that the steam wand assembly 100 and various alternative embodiments may be operatively associated with any other type of machine or appliance that is suitable for the provision of steam to heat liquids. In some configurations, the steam wand assembly 100 may be provided in a standalone device or machine.

[0051] The wand body 102 includes an outer housing 110 and a number of internal components of the assembly 100 may be located substantially within or surrounded by the outer housing 110. The outer housing 110 may be in the form of an elongated hollow tube or shaft having an internal bore defined by an inner bore wall. In the embodiment shown, the outer housing 110 extends firstly along a main (central) longitudinal axis 112 and then bends or extends at an angle along one or more additional axes 114, 115. It will, however, be appreciated that the shape and configuration of the outer housing 110 is not necessarily limited to the shape and configuration as described and shown in the drawings, and may be customised or adjusted depending on the design requirements of the assembly 100. In some embodiments, the outer housing 110 may extend only along the main longitudinal axis 112 to form a straight line tube. The outer housing 110 may be formed from a stainless steel material, chromed material, ceramic material, or the like.

[0052] In the depicted embodiment, the internal components of the assembly 100 may include a temperature sensor assembly including a temperature sensor 120 mounted to a main body 122, a sensor holder 124, and a sensor seal 126. The main body 122 may in turn be mounted to the steam wand body 102, as will be discussed further below. The temperature sensor 120 may be in the form of an NTC thermistor and the sensor seal 126 may be in the form of a silicone tip or part disposed, preferably radially, between the temperature sensor 120 and the nozzle assembly 104. The sensor seal 126 is adapted to seal the temperature sensor 120 from water and / or steam that is being communicated via a steam path of the steam wand assembly 100.

[0053] The main body 122 may have a generally cylindrical or tubular arrangement and may include an outer wall having an external threaded portion 128 to be coupled with a corresponding internal threaded portion 129 on the inner bore wall of the outer housing 110,thereby providing a connection between the main body 122 and the outer housing 110. During assembly and dis-assembly, the main body 122 may be rotated about the longitudinal axis 112 to allow the main body 122 to be threadably engaged with the outer housing 110. In other embodiments, and as will be described in further detail below, the main body 122 may be mounted to the steam wand body 102 / the outer housing 110 via other attachment or coupling techniques, depending on the design requirements of the steam wand assembly 100. The main body 122 may further include one or more projections 130 that are adapted to be received in one or more corresponding slots or openings 132 in the sensor holder 124, thereby providing the connection or coupling between the main body 122 and the sensor holder 124. The sensor holder 124 may also provide the connection between the sensor seal 126 and the main body 122, as will be described in further detail below.

[0054] The main body 122 may further include an inner wall portion or partition 134 that separates a steam path or cavity 136 from a wiring path or cavity 138 of the main body 122. The inner wall portion 134 may have one or more ramps to facilitate the separation between the two paths or cavities. When viewed from the side (e.g. as shown in Figure 3), the main body 122 may be visualised as having an upper plane A, a central plane B, and a lower plane C. In this example, the outer wall of the main body 122 extends along both the upper and lower planes A, C due to its generally cylindrical or tubular nature, and the inner wall portion 134 extends between the upper and lower planes A, C. In the depicted embodiment, the inner wall portion 134 firstly extends diagonally from the upper plane A to the central plane B to form a first ramp, then extends along linearly along the central plane B, and then extends diagonally from the central plane B to the lower plane C to form a second ramp. The arrangement of the ramped inner wall portion 134 may therefore separate the two paths or cavities into two longitudinally adjacent portions, i.e. a left side portion and a right side portion along the central axis 112 (when the steam wand assembly 100 is oriented horizontally, e.g. as shown in the Figures) or into an upper side portion and a lower side portion (when the steam wand assembly 100 is oriented vertically). It will be understood that in some embodiments, the configuration of the inner wall portion 134 is not necessarily limited to the configuration as shown in the drawings or described above, and may be adjusted depending on the design requirements of the steam wand assembly 100. For example, in some embodiments (not shown), the inner wall portion 134 may include a single ramp that extends diagonally between the upper plane A and the lower plane C.

[0055] In this arrangement of the ramped inner wall portion 134 and when viewed from the side, the steam path or cavity 136 is disposed on or about the underside of (i.e. below) the inner wall portion 134 and in the right side portion, whilst the wiring path or cavity 138 is disposed on or about the upperside of (i.e. above) the inner wall portion 134 and in the left side portion. It will be appreciated that the arrangement of the ramped inner wall portion 134 may at least allow for the steam path or cavity 136 and the wiring path or cavity 138 to be located in closer proximity to the central axis 112 as they are arranged in a side-by-side or intertwined manner (thus taking up less space), instead of in parallel (which necessitates a larger width / diameter of the steam wand assembly 100). The arrangement of the ramped inner wall portion 134 may therefore reduce the overall width / diameter of the steam wand assembly 100. As will be discussed in further detail below, this arrangement may also allow for the temperature sensor 120 (which is disposed in the wiring path or cavity 138) to be located at the center of the steam wand body 102 / steam wand assembly 100, with the temperature sensor 120 being centrally aligned along the axis 112.

[0056] In the embodiment shown, the steam path 136 provides a path for fluid communication between one or more steam / nozzle outlets 139 of the nozzle assembly 104 which lead to the atmosphere and an inner steam tube or hose 140, which is connected to the main body 122 to allow for the provision of steam from the milk frothing device or the milk frothing module to the steam wand assembly 100. The steam path 136 may include a steam path outlet 137 for steam delivery to the one or more steam / nozzle outlets 139. One or more O-ring seals or gaskets 142 may be provided at the interface between the steam tube 140 and the main body 122 to facilitate the connection and / or sealing therebetween. The wiring path 138 likewise provides a path for electrical communication between the temperature sensor 120 and circuitry of the milk frothing device or the milk frothing module (not shown) via one or more wires 143. The wiring path 138 may extend to an opening 144 and an accompanying external channel 145 located in a sidewall of the main body 122, thereby allowing the one or more wires 143 to extend through the opening 144 and rest along the external channel 145 as they connect to the coffee machine circuitry.

[0057] It will be appreciated that the inner wall portion 134 of the main body 122 may provide a separation or barrier between wet steam that is being communicated via the steam path 136 and sensitive electrical connections for the temperature sensor 120 which are located within thewiring path 138. The inner wall portion 134 may also allow for the temperature sensor 120 to be positioned at the tip of the steam wand assembly 100 (and centrally aligned along the axis 112). As will be appreciated at least from the Figures, the steam path outlet 137 is arranged so that it is in reasonably close proximity to the tip of the steam wand assembly 100 (and in reasonably close proximity behind the temperature sensor 120), which may result in a more compact or shortened cavity length within the steam wand assembly 100. The steam tube 140 may also include an outlet 141 that is in reasonably close proximity to the tip of the steam wand assembly 100 (and in reasonably close proximity behind the temperature sensor 120). The above arrangement may effectively allow for the various internal components of the steam wand assembly 100 to be shifted closer together (and also closer to the central longitudinal axis 112) as compared to conventional steam wand arrangements. One advantage of a shortened cavity length is that the surface area for steam condensation within the wand assembly 100 may be minimised. This may at least reduce the likelihood or opportunity for the steam to turn back into water within the cavity, thereby minimising the dilution of the milk being steamed / frothed.

[0058] In some embodiments, a first relief channel 146 may be provided at an interface between the main body 122 and the outer housing 110. In the embodiment shown, the first relief channel 146 is a flat or unthreaded portion that is formed in the inner bore wall of the outer housing 110, and is located adjacent to the internal threaded portion 129. The first relief channel 146 may at least create a shoulder 147 that allows the adjoining portion of the main body 122 to be fully “seated” within the internal bore of the outer housing 110 and minimise or avoid an issue commonly known as “thread run out” in typical assemblies, where it is difficult to control where threads start and end. The provision of the first relief channel 146 may at least remove the need to have a “like for like” match of the threads of the external threaded portion 128 of the main body 122 and the threads of the internal threaded portion 129 of the outer housing 110. Any left-over threads are not impeded from seating as the first relief channel 146 may take the place of the otherwise impeding material of the outer housing 110.

[0059] The nozzle assembly 104 in the depicted embodiment includes a nozzle body 150 and a nozzle cover 152. The nozzle assembly 104 may further include one or both of a first nozzle seal 154 and a second nozzle seal 156. The nozzle body 150 may rest against or abut the main body 122. Similar to the main body 122, the nozzle body 150 may include one or more external threaded portions 158 to be coupled with the corresponding internal threaded portion 129 of theouter housing 110, thereby providing a connection between the nozzle body 122 and the outer housing 110. During assembly and dis-assembly, the nozzle body 150 may be rotated about the longitudinal axis 112 to allow the nozzle body 150 to be threadably engaged with the outer housing 110.

[0060] The nozzle cover 152 may include an inner bore wall having an internal threaded portion 159 adapted to be coupled with one of the external threaded portions 158 of the nozzle body 150, thereby providing a connection between the nozzle cover 152 and the nozzle body 150. During assembly and dis-assembly, the nozzle cover 152 may be rotated about the longitudinal axis 112 to allow the nozzle cover 152 to be threadably engaged with the nozzle body 150. The first nozzle seal 154 and the second nozzle seal 156 may each be located at an interface between the nozzle assembly body 150 and the nozzle cover 152, thereby providing a seal therebetween. Accordingly, it will be appreciated that the first and / or second nozzle seals 154 and 156 may at least protect or seal against liquid ingress between the nozzle assembly body 150 and the nozzle cover 152.

[0061] The steam wand assembly 100 may further include nozzle to wand seal 160 located at an interface between the nozzle assembly 104 and the steam wand body 102. In the depicted embodiment, the nozzle to wand seal 160 is provided to seal the nozzle body 150 against the outer housing 110 of the steam wand body 102. The nozzle body 150 may also include a flange portion 161 that separates the nozzle cover 152 and the outer housing 110.

[0062] The steam wand assembly 100 may further include a main body seal 162 also located at an interface between the nozzle assembly 104 and the steam wand body 102. In the depicted embodiment, the main body seal 162 is provided to seal the nozzle body 150 against the main body 122.

[0063] Each of the seals described above (i.e. the first nozzle seal 154, the second nozzle seal 156, the nozzle to wand seal 160, and the main body seal 162) may include one or more radially outwardly projecting flanges or protrusions to enhance the sealing functionality thereof. The radially outwardly projecting flanges or protrusions may be spaced apart from one another by a distance. Each of the seals described above are adapted to seal against ingress or egress of steam and / or liquid.

[0064] With the arrangement of the nozzle to wand seal 160, for example, it is envisaged that the improved sealing functionality that is provided between nozzle body 150 and the outer housing 110 of the steam wand body 102 may at least reduce or altogether remove the reliance on the user to tighten the nozzle assembly 104 to the steam wand body 102 during re-assembly after cleaning. In one preferred arrangement, the nozzle to wand seal 160 may have a width that is greater than a width of the number of threads / thread pitch required to disengage the nozzle assembly 104 from the steam band body 102. In other words, a tolerance may be afforded by the width of the nozzle to wand seal 160. For example, if each thread pitch / pitch turn is 1 mm, it takes at least 3 turns before the seal is no longer in contact, so a user can loosely thread the nozzle assembly 104 and steam wand body 102 together and still achieve sealing. The nozzle to wand seal 160 may compress onto the inner bore wall of the nozzle body 150 to maintain contact with the nozzle to wand seal 160 along the length of the face, which is understood to be greater than the amount of threading required to disengage the nozzle assembly 104, such that, even if the user does not completely tighten the threads of the nozzle body 150, the nozzle to wand seal 160 may at least create enough sealing to adequately seal the nozzle body 150 to the outer housing 110 of the steam wand body 102.

[0065] The nozzle body 150 and the main body 122 may each include one or more locating portions to accommodate the associated seals. By way of non-limiting example, and as best shown in Figure 2, the nozzle body 150 may include a first nozzle seal locating portion 164 and a second nozzle seal locating portion 166 to accommodate the first and second nozzle seals 154 and 156, respectively. The nozzle body 150 may further include a nozzle to wand seal locating portion 168 to accommodate the nozzle to wand seal 160. The main body 122 may likewise include a main body seal locating portion 169 to accommodate the main body seal 162.

[0066] Similar to the arrangement of the first relief channel 146 described above, in some embodiments, a second relief channel 170 may be provided at an interface between the nozzle body 150 and the nozzle cover 152. In the embodiment shown, the second relief channel 170 is a flat or unthreaded portion that is formed in the inner bore wall of the nozzle cover 152, and is located adjacent to the internal threaded portion 159. The second relief channel 170 may at least create a shoulder 171 that allows the adjoining portion of the nozzle body 150 to be fully “seated” within the internal bore of the nozzle cover 152 and minimise or avoid an issue of thread run out. The provision of the second relief channel 170 may at least remove the need tohave a “like for like” match of the threads of the external threaded portion 158 of the nozzle body 150 and the threads of the internal threaded portion 159 of the nozzle cover 152. Any leftover threads are not impeded from seating as the second relief channel 170 may take the place of the otherwise impeding material of the outer housing 110.

[0067] Returning to the sensor holder 124, and as mentioned above, the sensor holder 124 provides the connection between the sensor seal 126 and the main body 122. In the embodiment shown, the sensor holder 124 (which may include the one or more slots or openings 132 that receives the one or more corresponding projections 130 of the main body 122) is adapted to retain or “clip” the sensor seal 126 (and in turn the temperature sensor 120) in place relative to the main body 122. To facilitate this retention or clipping, the sensor holder 124 may also include inner portions that are connectable to corresponding outer portions of the sensor seal 126. With this arrangement, the sensor seal 126 and the main body 122 may each be in direct contact with the temperature sensor 120, thereby allowing the temperature sensor 120 to be adequately sealed and / or secured. It will be appreciated that the cooperation between the main body 122 and the sensor holder 124 allows the sensor seal 126 to be retained (along with the temperature sensor 120), thereby removing the need for a secondary seal as will be discuss in further detail below.

[0068] It will be appreciated that, with the arrangement of the sensor holder 124 described above, more than one function may be achieved by a single component and as such, in the example provided, a secondary seal is not required. In typical steam wand arrangements, the presence of the secondary seal is undesirable as it has a thickness that increases the overall diameter of the steam wand. With the arrangement of the steam wand assembly 100 described above, the number of required materials may be minimised, which may simplify the construction of the steam wand assembly 100, and the overall diameter of the steam wand assembly 100 may also be reduced. Reducing the overall diameter of the steam wand assembly 100 may at least allow the user to have a larger field of vision when monitoring the steaming / frothing of the milk. Additionally, reducing the overall length of the steam wand assembly 100 may at least reduce the likelihood of condensation within the steam wand. It will also be appreciated that the above arrangements may at least create a compact solution which may be more adaptable and optimised in respect of materials and cost of parts.

[0069] Referring to Figure 4, a visual advantage of reducing the overall diameter of the steam wand assembly 100 is shown. With a reduced overall diameter Do, the pitch circle diameter Dp of the steam / nozzle outlets 139 can in turn be brought closer to the central longitudinal axis of the steam wand assembly 100 (corresponding to the main longitudinal axis 112 described above). With this arrangement, the steam that is provided by the steam wand assembly 100 may be more streamlined and focused and at a higher velocity. In particular, a length L between the tip of the nozzle assembly 104 and the wand body 102 may be reduced. As discussed above, it will be appreciated that a reduced overall length of the steam wand assembly 100 may at least allow for adaptability of the arrangement for a variety of steam wand arrangements. In one exemplary embodiment, the overall diameter Do of the steam wand assembly 100 may be between approximately 14 and 17 mm, and the pitch circle diameter Dp of the steam / nozzle outlets 139 may be between approximately 5 and 7 mm. In one exemplary embodiment, the length L between the tip of the nozzle assembly 104 and the wand body 102 may be between approximately 50 and 55 mm. It will, however, be appreciated that the dimensions of the steam wand assembly 100 and components thereof are not necessarily limited to the dimensions as described above, and may be customised or adjusted depending on the design requirements of the assembly 100.

[0070] In the depicted embodiment, each of the steam nozzle / outlets 139 is arranged to extend in a parallel orientation relative to the central longitudinal axis 112. It is envisaged that in other embodiments (not shown), each steam nozzle / outlet 139 may alternatively be arranged to extend at an angle relative to and away from the central longitudinal axis 112. The angle of extension of each steam nozzle / outlet 139 may be anywhere between approximately 0 to 90 degrees relative to the central longitudinal axis 112, and preferably less than approximately 45 degrees relative to the central longitudinal axis 112. In some embodiments, the angle of extension of each steam nozzle / outlet 139 may be approximately 15 degrees relative to the central longitudinal axis 112. It will be appreciated that angling the steam nozzle / outlets 139 away from the central longitudinal axis 112 (i.e. instead of arranging them parallel to the central longitudinal axis 112) may at least allow for steam to exit the steam wand assembly 100 further away from the temperature sensor 120 (which is located on the central longitudinal axis 112). It is understood that in arrangements whereby the steam nozzle / outlets 139 are arranged parallel to the central longitudinal axis 112 (and therefore closer to the temperature sensor 120), there is a potential for the steam to push the milk away from the temperature sensor 120 as it exits thesteam wand assembly 100, which may cause incorrect or inconsistent temperature readings at the temperature sensor 120 (e.g. by pushing away the hotter milk whilst the colder milk curdles to the temperature sensor 120). Accordingly, by angling the steam nozzle / outlets 139 away from the central longitudinal axis 112 (i.e. instead of arranging them parallel to the central longitudinal axis 112), the milk may be more homogenously spread out and evenly mixed during frothing as a temperature reading is taken at the temperature sensor 120. This arrangement may thus reduce potential errors or inconsistencies in the temperature reading, and may result in less variations between temperature readings. The arrangement of the steam nozzle / outlets 139 (parallel or angled) may be selected, depending on the requirements of the steam wand assembly 100. For example, it is envisaged that the angled arrangement of the steam nozzle / outlets 139 may be particularly beneficial for frothing smaller volumes (e.g. 250 mL) of milk.

[0071] It will further be appreciated that certain components of the steam wand assembly 100 may be formed from a high temperature polymer material to reduce the heat transfer from the steam path 136 to the nozzle cover 152 and the outer housing 110 (which are typically formed from stainless steel). In particular, it is envisaged that each of the main body 122, the sensor holder 124, and the nozzle body 150 may be formed from a high temperature polymer material. It will, however, be appreciated that other components of the steam wand assembly 100 described herein and as shown in the drawings may also be formed from a high temperature polymer, depending on the design requirements of the assembly 100.

[0072] With conventional stainless steel steam wand arrangements of known devices, the conductive heat transfer from the steam creates a hot surface on both the exterior and the interior of the steam wand assembly. These hot surfaces are susceptible to becoming stuck with milk proteins and sugars, which may result in an undesirable “cooking” of such proteins on the steam wand assembly. By insulating the delivery of steam internally through the inner steam tube 140 and delivery of the steam within the nozzle assembly 104 with the use of high temperature polymer materials, the likelihood of “cooking” the protein onto the steam wand assembly 100 may be reduced. This arrangement may also allow the external surface of the steam wand assembly 100 to have a relatively lower temperature for improved safety, which may less the severity or likelihood of a user burning their skin when touching the steam wand assembly 100.

[0073] Returning to the steam path 136 and the wiring path 138, it will further be appreciated that, by attaching the temperature sensor 120 and the sensor seal 126 directly to the main body 122, both the steam path 136 and the wiring path 138 may be positioned closer to the central longitudinal axis 112. The arrangement of the inner wall portion 134 of the main body 122 (which separates the steam path 136 from the wiring path 138) may allow the temperature sensor 120 to be positioned closer to the tip of the steam wand assembly 100. As discussed above, the steam path outlet 137 of the steam path 136 may also be arranged so that it is reasonably close to the tip of the steam wand assembly 100 (and reasonably close behind the temperature sensor 120). Accordingly, with this arrangement, the overall length and the distance of the steam path 136 between the inner steam tube 140 and the steam / nozzle outlet(s) 139 may be reduced. The steam path outlet 137 may thus deliver steam closer to the steam / nozzle outlet(s) 139. It will be appreciated that the location of the steam path outlet 137 may correspond to the length of the temperature sensor 120. In one example, if the length of the temperature sensor 120 is shortened by a distance, the location of the steam path outlet 137 relative to the steam / nozzle outlet(s) 139 will also be shortened by a corresponding distance.

[0074] In Figures 5 to 7 of the accompanying drawings, there is schematically depicted a further embodiment of a steam wand assembly 100 A which operates in generally similar manner as the steam wand assembly 100 described above, with like reference numerals being used to indicate like features. In the interest of clarity, not all like features will be accorded a like reference numeral in the drawings, the description of the like features of this embodiment will not be repeated, and it will be understood that any one or more of the like features or functions of the embodiment of the steam wand assembly 100 described above are applicable to the embodiment of the steam wand assembly 100 A, and vice versa.

[0075] In this embodiment of the steam wand assembly 100A, a lock nut 172A is provided as a separately formed component to replace the external threaded portion 128 of the main body 122 described above. Accordingly, in this embodiment, the main body 122A does not include an external threaded portion for connecting the main body 122 A to the outer housing 110A. Instead, the lock nut 172 A is provided with an external threaded portion 174 A to be coupled with the corresponding internal threaded portion 129 A of the outer housing 110A, thereby providing a connection between the main body 122A and the outer housing 110A. With this arrangement, the separately formed threaded lock nut 172A may alleviate potential issuesarising from twisting of electrical components (such as the wires 143 A of the temperature sensor 120A) during assembly or dis-assembly of the steam wand assembly 100A.

[0076] In this arrangement of the steam wand assembly, the first relief channel 146A may be provided at an interface between the lock nut 172 A and the outer housing 110A. In the embodiment shown, the first relief channel 146A is a flat or unthreaded portion that is formed in the inner bore wall of the outer housing 110A, and is located adjacent to the internal threaded portion 129 A of the outer housing 110A. The first relief channel 146 A may at least create a shoulder 147A that allows the adjoining portion of the lock nut 172A to be fully “seated” within the internal bore of the outer housing 110A and mimimise or avoid an issue of thread run out. The provision of the first relief channel 146A may at least remove the need to have a “like for like” match of the threads of the external threaded portion 174 A of the lock nut 172 A and the threads of the internal threaded portion 129 A of the outer housing 110A. Any left-over threads are not impeded from seating as the first relief channel 146A may take the place of the otherwise impeding material of the outer housing 110A.

[0077] In Figure 8 of the accompanying drawings, there is schematically depicted a further embodiment of a steam wand assembly 100B which operates in generally similar manner as the steam wand assemblies 100 and 100A described above, with like reference numerals being used to indicate like features. In the interest of clarity, not all like features will be accorded a like reference numeral in the drawings, the description of the like features of this embodiment will not be repeated, and it will be understood that any one or more of the like features or functions of the embodiment of the steam wand assemblies 100 and 100 A described above are applicable to the embodiment of the steam wand assembly 100B, and vice versa.

[0078] In this embodiment of the steam wand assembly 100B, the sensor holder 124B rests against or abuts the main body 122B, and a radial lip seal 178B is provided at an interface between the sensor holder 124B and the main body 122B. The radial lip seal 178B may include a plurality of lips or protrusions / proj ections 179B to enhance sealing functionality. In this embodiment, the radial lip seal 178B with extending protrusions / proj ections 179B makes contact with both an inner bore face 18 IB of the main body 122B and an inner bore face 183B of the nozzle cover 152B. The protrusions / proj ections 179B may extend at an angle relative to a main body of the radial lip seal 178B. It will be understood that the direction of extension of theprotrusions / proj ections 179B relies on making contact with the inner bore face surfaces (i.e. the inner bore face 18 IB of the main body 122B and the inner bore face 183B of the nozzle cover 153B) for sealing. Further, pressure from steam internally of the steam wand assembly 100B may cause the radial lip seal 178B to also be under pressure, thereby allowing the radial lip seal 178B to press further against the inner bore faces. An O-ring seal 180B may be provided with the main body 122B to enhance sealing functionality. It will be appreciated that the main body 122B in this embodiment may include channel details to retain the O-ring seals 180B, thereby allowing the O-ring seal 180B to be reliably positioned in the steam wand assembly 100B.

[0079] In Figure 9 of the accompanying drawings, there is schematically depicted a further embodiment of a steam wand assembly 100C which operates in generally similar manner as the steam wand assemblies 100, 100A, and 100B described above, with like reference numerals being used to indicate like features. In the interest of clarity, not all like features will be accorded a like reference numeral in the drawings, the description of the like features of this embodiment will not be repeated, and it will be understood that any one or more of the like features or functions of the embodiment of the steam wand assemblies 100, 100 A, and 100B described above are applicable to the embodiment of the steam wand assembly 100C, and vice versa.

[0080] In this embodiment of the steam wand assembly 100C, a pair of O-ring seals 180C are be provided with the main body 122C to enhance sealing functionality. It is envisaged that the O-ring seals 180C may be reasonably large in diameter, thereby offering more compression against the end faces of the main body 122C and the nozzle cover 152C. In some embodiments, the O-ring seals 180C may have a diameter of approximately 3 to 4 mm. It will, however, be appreciated that the diameter of the O-ring seals 180C is not necessarily limited to the dimensions as described above, and may be customised or adjusted depending on the design requirements of the assembly 100C. In some embodiments, only one O-ring seal 180C may be provided, or more than a pair of O-ring seals 180C may be provided. It will be appreciated that the sensor body 124C in this embodiment may include channel details 125C to retain the O-ring seals 180C, thereby allowing the O-ring seals 180C to be reliably positioned in the steam wand assembly 100C and threaded towards the main body 122C. The O-ring seal 180C facing the nozzle cover 152C may be similarly compressed and sealed when the nozzle cover 152C is assembled.

[0081] In Figures 10 and 11 of the accompanying drawings, there is schematically depicted a further embodiment of a steam wand assembly 100D which operates in generally similar manner as the steam wand assemblies 100, 100A, 100B, and 100C described above, with like reference numerals being used to indicate like features. In the interest of clarity, not all like features will be accorded a like reference numeral in the drawings, the description of the like features of this embodiment will not be repeated, and it will be understood that any one or more of the like features or functions of the embodiment of the steam wand assemblies 100, 100 A, 100B, and 100C described above are applicable to the embodiment of the steam wand assembly 100D, and vice versa.

[0082] In this embodiment of the steam wand assembly 100D, the sensor seal 126D includes a self-retaining or “clip over” feature 182D to facilitate the connection of the sensor seal 126D to the temperature sensor 120D. The sensor seal 126D may include a circumferential groove or channel that receives a corresponding circumferential projection of the temperature sensor 120D. The circumferential groove or channel of the sensor seal 126D cooperates with the corresponding circumferential projection of the temperature sensor 120D, which may at least an enable the sensor seal 126D to be assembled directly to the body of the temperature sensor 120D. This arrangement may at least simplify the assembly. The sensor seal 126D may also include a longer flange portion or seal face 185D that is in contact with the body of the temperature sensor 120D. This flange portion or seal face 185D may at least push onwards and seal against the internal surface of the main body 122D. This arrangement may allow for more robust sealing against the body of the temperature sensor 120D and against the internal surface of the main body 122D.

[0083] In Figures 12 to 17 of the accompanying drawings, there is schematically depicted a further embodiment of a steam wand assembly 100E which operates in generally similar manner as the steam wand assemblies 100, 100A, 100B, 100C, and 100D described above, with like reference numerals being used to indicate like features. In the interest of clarity, not all like features will be accorded a like reference numeral in the drawings, the description of the like features of this embodiment will not be repeated, and it will be understood that any one or more of the like features or functions of the embodiment of the steam wand assemblies 100, 100 A, 100B, 100C, and 100D described above are applicable to the embodiment of the steam wand assembly 100E, and vice versa.

[0084] In this embodiment of the steam wand assembly 100E, the lock nut 172E is provided as a separately formed component of the main body 122E. The sensor holder 124E sits on to the main body 122E, and is then secured by the lock nut 172E. Similar to one or more of the embodiments described above, the lock nut 172E is provided with an external threaded portion to be coupled with a corresponding internal threaded portion of the outer housing 110E, thereby providing the connection between the main body 122E and the outer housing 110A. With this arrangement, the separately formed threaded lock nut 17E may alleviate potential issues arising from twisting of electrical during assembly or disassembly of the steam wand assembly 100E.

[0085] A method of manufacturing or forming the main body 122 of the embodiment of the steam wand assembly 100 above will now be described with reference to Figures 18 to 20. It will be understood that this method may be similarly applied in respect of the other embodiments of the steam wand assembly (100A, 100B, etc.) described above and as shown in the drawings. In Figure 18, a mould tool assembly 200 for the main body 122 is depicted, with the assembly 200 including a cavity side tool 205 and a core side tool 210. It will be understood that the cavity side tool 205 and the core side tool 210 define the two main halves of the mould tool assembly 200 for forming the main body 122. The main body 122 may be oriented along a length of the cavity side tool 205 and the core side tool 210. An example of a main body 122 moulded using the mould tool assembly 200 is depicted in Figure 19, whilst an example of a main body 122 in a further post-moulded state is depicted in Figure 20.

[0086] The steam path 136 and the wiring path 138 of the main body 122 may be formed by two moving (sliding) cores, being tool core pins 215 and 220. As best shown in Figure 13, the cavities in the main body 122 that form the steam path 136 and the wiring path 138 are offset from one another and do not meet - this would be an example of an arrangement when shut-offs are desired to create openings in the moulded part of the main body 122. As discussed above, the steam path 136 and the wiring path 138 are separated by the inner wall portion 134. The two sliding cores (tool core pins 215 and 220) create the blind holes or cavities inside the moulded part of the main body 122, also forming the inner wall portion 134, as well as the steam path 136 and the wiring path 138. During the moulding process, walls 225 and 230 (for the steam path 136 and the wiring path 138, respectively) are formed. The walls 225 and 230 may be oriented transverse to the longitudinal axis of the main body 122.

[0087] It will be appreciated that one reason for not creating shut-offs with the moving (sliding) cores and with the cavity side tool 205 and the core side tool 210 of the mould assembly 200 is that it may create significant pressure from the tool steel contact (to achieve tooling shut off) and injection pressures of the polymer. Further, owing to the size of the main body 122 that is to be moulded, the tooling would be relatively small. This exerts a lot of force on the moving (sliding) cores and is likely to break during moulding. To at least reduce the reliance on high precision tooling and moulding (which typically requires specialist skills and higher part costs), the mould tool assembly 200 intentionally creates a blind cavity, which leaves a connecting wall (i.e. walls 225, 230) of polymer between the core and tool steel from the cavity side tool 205 and the core side tool 210 when polymer is injected into the mould.

[0088] Following moulding, the moulded part of the main body 122 may be ejected in the same manner as traditional tooling processes. The partially formed geometry (walls 225, 230) for the steam path 136 and the wiring path 138 will be moulded into the part. The part may then be placed into a CNC machine center, so that the remnant walls can be removed by drilling holes from the steam and wiring path ends, leaving behind the respective open paths for steam and wiring.

[0089] The method of manufacturing or forming the moulded part of the main body 122 may thus be summarised by way of the following steps:• Forming a mould tool assembly 200 having a cavity side tool 205 and a core side tool 210, with each of the cavity side tool 205 and the core side tool having cavities corresponding to the respective half / portion of the main body 122.• Forming moving (sliding) cores having two protrusions (i.e. tool core pins 215 and 220) in the mould tool assembly 200.• Closing / assembling the cavity side tool 205 and the core side tool 210 along a first (longitudinal) axis to form a first part of a mould for the external surfaces of the main body 122.• Closing / assembling the two tool core pins 215 and 220 along a second (transverse) axis to form a second part of the mould for the two cavities within the main body 122.• Injecting heated plastic (polymer) into the mould tool assembly 200.• Generating the wall 230 between the cavity side tool 205 and the first tool core pin 215 and likewise, generating the wall 225 between the cavity side tool 210 and the second tool core pin 220.• Opening / disassembling the cavity side tool 205 and the core side tool 210 along the first axis and opening / disassembling and the tool core pins 215 and 220 along the second axis,• Optionally removing the walls 225, 230 by way of a drilling process, CNC machine routing, or the like to generate the steam path 136 and the wiring path 138, respectively.

[0090] It is envisaged that other methods of manufacturing or forming the main body 122 may involve 3D printing the main body 122, for example.

[0091] Although specific embodiments of the invention are illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternative and / or equivalent implementations exist. It should be appreciated that the exemplary embodiment or exemplary embodiments are examples only and are not intended to limit the scope, applicability, or configuration in any way. Rather, the foregoing summary and detailed description will provide those skilled in the art with a convenient road map for implementing at least one exemplary embodiment, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope as set forth in the appended claims and their legal equivalents. Generally, this application is intended to cover any adaptations or variations of the specific embodiments discussed herein.

[0092] It will also be appreciated that in this document the terms “comprise”, “comprising”, “include”, “including”, “contain”, “containing”, “have”, “having”, and any variations thereof, are intended to be understood in an inclusive (i.e. non-exclusive) sense, such that the process,method, device, apparatus or system described herein is not limited to those features or parts or elements or steps recited but may include other elements, features, parts or steps not expressly listed or inherent to such process, method, article, or apparatus. Furthermore, the terms “a” and “an” used herein are intended to be understood as meaning one or more unless explicitly stated otherwise. Moreover, the terms “first”, “second”, etc. are used merely as labels, and are not intended to impose numerical requirements on or to establish a certain ranking of importance of their objects.

Claims

CLAIMS1. A steam wand assembly including: a steam wand body defining a central longitudinal axis; a nozzle assembly located at an end portion of the steam wand body; a temperature sensor assembly located adjacent to the nozzle assembly, the temperature sensor assembly including: a main body mounted to the steam wand body; a temperature sensor mounted to the main body; a sensor seal located between the temperature sensor and the nozzle assembly; and a sensor holder coupled to the main body and the sensor seal and adapted to secure the temperature sensor within the steam wand body.

2. The steam wand assembly according to claim 1, wherein the main body includes a cavity providing a steam path for delivery of steam to the nozzle assembly and a wiring path for electrical communication to the temperature sensor.

3. The steam wand assembly according to claim 2, wherein the steam path includes a steam path outlet located in close proximity to the temperature sensor.

4. The steam wand assembly according to claim 2 or 3, wherein the main body includes an inner wall portion to separate the steam path and the wiring path into two longitudinally adjacent portions.

5. The steam wand assembly according to claim 4, wherein the inner wall portion includes one or more ramps to facilitate the separation between the steam path and the wiring path.

6. The steam wand assembly according to claim 4 or 5, wherein the main body has a generally tubular arrangement having an upper plane, a central plane, and a lower plane, with the outer wall of the main body extending along the upper and lower planes.

7. The steam wand assembly according to claim 6, wherein the inner wall portion extends diagonally between the upper plane and the lower plane to form a ramp.

8. The steam wand assembly according to claim 6, wherein the inner wall portion extends diagonally from the upper plane to the central plane to form a first ramp, then linearly along the central plane, then diagonally from the central plane to the lower plane to form a second ramp.

9. The steam wand assembly according to any one of the preceding claims, wherein the temperature sensor is mounted to the main body so as to be centrally aligned with the steam wand body.

10. The steam wand assembly according to any one of the preceding claims, wherein the sensor holder is coupled to an outer portion of the sensor seal and an outer wall of the main body.

11. The steam wand assembly according to any one of the preceding claims, wherein the sensor holder includes one or more slots or openings adapted to receive one or more corresponding projections of the main body.

12. The steam wand assembly according to any one of the preceding claims, wherein the main body and the sensor holder cooperate to retain the sensor seal and the temperature sensor in place within the steam wand body.

13. The steam wand assembly according to any one of the preceding claims, wherein the temperature sensor and the sensor seal are attached directly to the main body.

14. The steam wand assembly according to any one of the preceding claims, wherein the nozzle assembly includes a nozzle body threadably coupled to the main body.

15. The steam wand assembly according to claim 14, further including a nozzle seal located between the nozzle body and the main body for sealing the nozzle assembly.

16. The steam wand assembly according to any one of the preceding claims, wherein the main body is threadably coupled to an outer housing of the steam wand body.

17. The steam wand assembly according to claim 16, wherein the main body is coupled to the outer housing by way of a locking nut.

18. The steam wand assembly according to any one of the preceding claims, wherein an inner bore wall of the outer housing includes a threaded portion and a relief channel that creates a shoulder adjacent the threaded portion.

19. The steam wand assembly according to any one of the preceding claims, further including a steam tube connected to the main body, the steam tube having an outlet located in close proximity to the temperature sensor.

20. The steam wand assembly according to any one of the preceding claims, wherein the main body, the sensor holder, and / or the nozzle body are formed from a high temperature polymer material.

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